【转载】sql-builder介绍
原文链接：sql-builder介绍
关于sql-builder
sql-builder尝试使用java对象，通过类SQL的拼接方式，动态快速的生成SQL。它可作为稍后的开源项目ibit-mybatis的核心类库。
sql-builder提供了对象拼接的构造类Sql和字符串拼接的构造类StringSql。
Sql构造示例
详细测试用例查看：tech.ibit.sqlbuilder.SqlTest
select
// 传入列
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name))
.from(UserProperties.TABLE);
assertParamsEquals("SELECT u.user_id, u.name FROM user u", sql.getSqlParams());
// 支持聚合函数
sql = new Sql().select(Arrays.asList(new SumColumn(UserProperties.userId, "user_id_sum")
, new AvgColumn(UserProperties.userId, "user_id_avg")))
.from(UserProperties.TABLE).groupBy(UserProperties.userId);
assertParamsEquals("SELECT SUM(u.user_id) AS user_id_sum, AVG(u.user_id) AS user_id_avg FROM user u GROUP BY u.user_id"
, sql.getSqlParams());
selectDistinct
Sql sql = new Sql()
.selectDistinct(UserProperties.email)
.from(UserProperties.TABLE);
assertParamsEquals("SELECT DISTINCT u.email FROM user u", Collections.emptyList(), sql.getSqlParams());
selectPo（解析传入类）
Sql sql = new Sql()
.selectPo(UserPo.class)
.from(UserProperties.TABLE);
assertParamsEquals("SELECT u.user_id, u.login_id, u.email, u.mobile_phone, u.type FROM user u",
Collections.emptyList(), sql.getSqlParams());
selectDistinctPo
Sql sql = new Sql()
.selectDistinctPo(UserPo.class)
.from(UserProperties.TABLE).limit(1000);
assertParamsEquals("SELECT DISTINCT u.user_id, u.login_id, u.email, u.mobile_phone, u.type FROM user u LIMIT ?, ?",
Arrays.asList("$start", 0, "$limit", 1000), sql.getSqlParams());
count
Sql sql = new Sql()
.count()
.from(UserProperties.TABLE);
assertParamsEquals("SELECT COUNT(*) FROM user u", sql.getSqlParams());
countDistinct
// 传入单列
Sql sql = new Sql()
.countDistinct(UserProperties.userId)
.from(UserProperties.TABLE);
assertParamsEquals("SELECT COUNT(DISTINCT u.user_id) FROM user u", sql.getSqlParams());
// 传入多列
sql = new Sql()
.countDistinct(Arrays.asList(UserProperties.name, UserProperties.email))
.from(UserProperties.TABLE);
assertParamsEquals("SELECT COUNT(DISTINCT u.name, u.email) FROM user u", sql.getSqlParams());
deleteFrom
// 删除操作必须包含where语句，不然这个操作很危险
Sql sql = new Sql().deleteFrom(UserProperties.TABLE);
thrown.expect(RuntimeException.class);
thrown.expectMessage("Where cannot be empty when do deleting!");
sql.getSqlParams();
// 正常删除
Sql sql = new Sql()
.deleteFrom(UserProperties.TABLE)
.andWhere(CriteriaItemMaker.equalsTo(UserProperties.userId, 1));
assertParamsEquals("DELETE FROM user WHERE user_id = ?",
Arrays.asList("user_id", 1), sql.getSqlParams());
deleteTableFrom（支持别名）
// 正常删除
Sql sql = new Sql()
.deleteTableFrom(UserProperties.TABLE)
.andWhere(CriteriaItemMaker.equalsTo(UserProperties.userId, 1));
assertParamsEquals("DELETE u.* FROM user u WHERE u.user_id = ?",
Arrays.asList("u.user_id", 1), sql.getSqlParams());
// 支持join的删除
sql = new Sql()
.deleteTableFrom(UserProperties.TABLE)
.andWhere(CriteriaItemMaker.equalsTo(UserProperties.userId, 1))
.leftJoinOn(OrganizationProperties.TABLE, Arrays.asList(UserProperties.orgId, OrganizationProperties.orgId));
assertParamsEquals("DELETE u.* FROM user u LEFT JOIN organization o ON u.org_id = o.org_id WHERE u.user_id = ?",
Arrays.asList("u.user_id", 1), sql.getSqlParams());
update
// update操作必须包含where语句，不然这操作很危险
Sql sql = new Sql()
.update(UserProperties.TABLE)
.set(new ColumnValue(UserProperties.name, "IBIT"));
thrown.expect(RuntimeException.class);
thrown.expectMessage("Where cannot be empty when do updating!");
sql.getSqlParams();
// 正常删除
sql = new Sql()
.update(UserProperties.TABLE)
.set(new ColumnValue(UserProperties.name, "IBIT"))
.andWhere(CriteriaItemMaker.equalsTo(UserProperties.userId, 1));
assertParamsEquals("UPDATE user u SET u.name = ? WHERE u.user_id = ?",
Arrays.asList("u.name", "IBIT", "u.user_id", 1), sql.getSqlParams());
insertInto & values
Sql sql = new Sql()
.insertInto(UserProperties.TABLE)
.values(Arrays.asList(new ColumnValue(UserProperties.name, "IBIT")
, new ColumnValue(UserProperties.loginId, "188")
, new ColumnValue(UserProperties.avatarId, null)));
assertParamsEquals("INSERT INTO user(name, login_id, avatar_id) VALUES(?, ?, ?)",
Arrays.asList("name", "IBIT", "login_id", "188", "avatar_id", null), sql.getSqlParams());
set
Sql sql = new Sql()
.update(UserProperties.TABLE)
.set(Arrays.asList(new ColumnValue(UserProperties.name, "IBIT")
, new ColumnValue(UserProperties.loginId, "188")
, new ColumnValue(UserProperties.avatarId, null)))
.andWhere(CriteriaItemMaker.equalsTo(UserProperties.userId, 1));
assertParamsEquals("UPDATE user u SET u.name = ?, u.login_id = ?, u.avatar_id = ? WHERE u.user_id = ?",
Arrays.asList("u.name", "IBIT", "u.login_id", "188", "u.avatar_id", null, "u.user_id", 1), sql.getSqlParams());
increaseSet(字段增长）
Sql sql = new Sql()
.update(UserProperties.TABLE)
.increaseSet(new ColumnValue(UserProperties.loginTimes, 2))
.andWhere(CriteriaItemMaker.equalsTo(UserProperties.userId, 1));
assertParamsEquals("UPDATE user u SET u.login_times = u.login_times + ? WHERE u.user_id = ?",
Arrays.asList("u.login_times", 2, "u.user_id", 1), sql.getSqlParams());
decreaseSet(字段递减)
Sql sql = new Sql()
.update(UserProperties.TABLE)
.decreaseSet(new ColumnValue(UserProperties.loginTimes, 2))
.andWhere(CriteriaItemMaker.equalsTo(UserProperties.userId, 1));
assertParamsEquals("UPDATE user u SET u.login_times = u.login_times - ? WHERE u.user_id = ?"
, Arrays.asList("u.login_times", 2, "u.user_id", 1), sql.getSqlParams());
from
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name, ProjectProperties.name))
.from(UserProperties.TABLE)
.from(ProjectProperties.TABLE)
.andWhere(CriteriaItemMaker.equalsTo(UserProperties.currentProjectId, ProjectProperties.projectId));
assertParamsEquals("SELECT u.user_id, u.name, p.name FROM user u, project p WHERE u.current_project_id = p.project_id",
Collections.emptyList(), sql.getSqlParams());
sql = new Sql()
.select(Arrays.asList(ProjectProperties.projectId, ProjectProperties.name))
.from(ProjectProperties.TABLE);
assertParamsEquals("SELECT p.project_id, p.name FROM project p",
Collections.emptyList(), sql.getSqlParams());
joinOn(left, right, full, inner)
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name, ProjectProperties.name))
.from(UserProperties.TABLE)
.joinOn(ProjectProperties.TABLE, Arrays.asList(UserProperties.currentProjectId, ProjectProperties.projectId));
assertParamsEquals("SELECT u.user_id, u.name, p.name FROM user u JOIN sz_project p ON u.current_project_id = p.project_id", sql.getSqlParams());
// left join on
sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name, ProjectProperties.name))
.from(UserProperties.TABLE)
.leftJoinOn(ProjectProperties.TABLE, Arrays.asList(UserProperties.currentProjectId, ProjectProperties.projectId));
assertParamsEquals("SELECT u.user_id, u.name, p.name FROM user u LEFT JOIN sz_project p ON u.current_project_id = p.project_id", sql.getSqlParams());
// 省略其他join
complexJoinOn(支持on后面增加条件，left, right, full, inner)
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name, ProjectProperties.name))
.from(UserProperties.TABLE)
.complexLeftJoinOn(ProjectProperties.TABLE, Collections.singletonList(CriteriaItemMaker.equalsTo(UserProperties.currentProjectId, ProjectProperties.projectId)));
SqlParams sqlParams = sql.getSqlParams();
assertEquals("SELECT u.user_id, u.name, p.name FROM user u LEFT JOIN project p ON u.current_project_id = p.project_id", sqlParams.getSql());
assertTrue(sqlParams.getParamDetails().isEmpty());
sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name, ProjectProperties.name))
.from(UserProperties.TABLE)
.complexLeftJoinOn(ProjectProperties.TABLE, Arrays.asList(
CriteriaItemMaker.equalsTo(UserProperties.currentProjectId, ProjectProperties.projectId),
CriteriaItemMaker.like(ProjectProperties.name, "小%")));
sqlParams = sql.getSqlParams();
assertEquals("SELECT u.user_id, u.name, p.name FROM user u LEFT JOIN project p "
+ "ON u.current_project_id = p.project_id AND p.name LIKE ?", sqlParams.getSql());
assertList(sqlParams.getParamDetails(), 1, Arrays.asList("p.name", "小%"));
// 省略其他join
where（支持构造复杂的where语句）
List<CriteriaItem> xiaoLikeItems = Arrays.asList(
CriteriaItemMaker.like(UserProperties.name, "小%"),
CriteriaItemMaker.like(UserProperties.email, "xiao%"));
CriteriaItem userIdItem = CriteriaItemMaker.greaterThan(UserProperties.userId, 100);
CriteriaItem type1Item = CriteriaItemMaker.equalsTo(UserProperties.type, 1);
CriteriaItem type2Item = CriteriaItemMaker.equalsTo(UserProperties.type, 2);
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name))
.from(UserProperties.TABLE)
.where(Criteria.ands(Arrays.asList(Criteria.ors(xiaoLikeItems), userIdItem)));
SqlParams sqlParams = sql.getSqlParams();
assertList(sqlParams.getParams(), 3, Arrays.asList("小%", "xiao%", 100));
sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name))
.from(UserProperties.TABLE)
.where(
Criteria.ands(
Arrays.asList(Criteria.ors(xiaoLikeItems),
Criteria.ors(Collections.singletonList(userIdItem)))
)
);
sqlParams = sql.getSqlParams();
assertParamsEquals("SELECT u.user_id, u.name FROM user u WHERE (u.name LIKE ? OR u.email LIKE ?) AND u.user_id > ?",
Arrays.asList("小%", "xiao%", 100), sqlParams);
sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name))
.from(UserProperties.TABLE)
.where(
Criteria.ors(Arrays.asList(
Criteria.ands(
Arrays.asList(Criteria.ands(
Arrays.asList(Criteria.ors(xiaoLikeItems),
Criteria.ors(Collections.singletonList(userIdItem)))),
type1Item)
), type2Item))
);
sqlParams = sql.getSqlParams();
assertParamsEquals("SELECT u.user_id, u.name FROM user u WHERE (((u.name LIKE ? OR u.email LIKE ?) AND u.user_id > ?) AND u.type = ?) OR u.type = ?",
Arrays.asList("小%", "xiao%", 100, 1, 2), sqlParams);
andWhere & orWhere & flag(支持标记位条件）
// and
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name))
.from(UserProperties.TABLE)
.andWhere(Criteria.ors(
Arrays.asList(CriteriaItemMaker.like(UserProperties.name, "小%"), CriteriaItemMaker.like(UserProperties.email, "xiao%"))))
.limit(1);
assertParamsEquals("SELECT u.user_id, u.name FROM user u WHERE (u.name LIKE ? OR u.email LIKE ?) LIMIT ?, ?"
, Arrays.asList("u.name", "小%", "u.email", "xiao%", "$start", 0, "$limit", 1), sql.getSqlParams());
// or
sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name))
.from(UserProperties.TABLE)
.orWhere(Criteria.ands(
Arrays.asList(CriteriaItemMaker.like(UserProperties.name, "小%"), CriteriaItemMaker.like(UserProperties.email, "xiao%"))))
.orWhere(CriteriaItemMaker.equalsTo(UserProperties.type, 1))
.limit(1);
assertParamsEquals("SELECT u.user_id, u.name FROM user u WHERE (u.name LIKE ? AND u.email LIKE ?) OR u.type = ? LIMIT ?, ?",
Arrays.asList("u.name", "小%", "u.email", "xiao%", "u.type", 1, "$start", 0, "$limit", 1), sql.getSqlParams());
// CriteriaItemMaker支持构造flag有：containsNoneFlags, containsAllFlags, containsAnyFlags
sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name))
.from(UserProperties.TABLE)
.andWhere(CriteriaItemMaker.containsNoneFlags(UserProperties.userId, 1));
assertParamsEquals("SELECT u.user_id, u.name FROM user u WHERE u.user_id & ? = 0",
Arrays.asList("u.user_id", 1), sql.getSqlParams());
orderBy
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name, ProjectProperties.name))
.from(UserProperties.TABLE)
.leftJoinOn(ProjectProperties.TABLE, Arrays.asList(UserProperties.currentProjectId, ProjectProperties.projectId))
.orderBy(Arrays.asList(new OrderBy(ProjectProperties.projectId), new OrderBy(UserProperties.userId, true)))
.limit(1000);
assertParamsEquals("SELECT u.user_id, u.name, p.name FROM user u LEFT JOIN project p ON u.current_project_id = p.project_id ORDER BY p.project_id, u.user_id DESC LIMIT ?, ?",
Arrays.asList("$start", 0, "$limit", 1000), sql.getSqlParams());
customerOrderBy（自定义排序：mysql语法）
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name, ProjectProperties.name))
.from(UserProperties.TABLE)
.leftJoinOn(ProjectProperties.TABLE, Arrays.asList(UserProperties.currentProjectId, ProjectProperties.projectId))
.orderBy(Arrays.asList(new OrderBy(ProjectProperties.projectId), new CustomOrderBy(UserProperties.userId, Arrays.asList(1, 2, 3), true)));
assertParamsEquals("SELECT u.user_id, u.name, p.name FROM user u LEFT JOIN project p ON u.current_project_id = p.project_id ORDER BY p.project_id"
+ ", FIELD(u.user_id, ?, ?, ?) DESC", Arrays.asList("u.user_id", 1, "u.user_id", 2, "u.user_id", 3), sql.getSqlParams());
nameOrderBy（自定义字段排序）
Sql sql = new Sql()
.select(
Arrays.asList(
new MinColumn(UserProperties.age, "min_age"),
new MaxColumn(UserProperties.age, "max_age"),
UserProperties.gender
))
.from(UserProperties.TABLE)
.andWhere(CriteriaItemMaker.greaterThanOrEqualsTo(UserProperties.age, 0))
.groupBy(UserProperties.gender)
.having(Having.and(HavingItemMaker.greaterThanOrEqualsTo("min_age", 1)))
.orderBy(Arrays.asList(
new OrderBy(UserProperties.gender),
new NameOrderBy("min_age", true)));
assertParamsEquals("SELECT MIN(u.age) AS min_age, MAX(u.age) AS max_age, u.gender FROM user u WHERE u.age >= ? " +
"GROUP BY u.gender HAVING min_age >= ? ORDER BY u.gender, min_age DESC", Arrays.asList("u.age", 0, "min_age", 1), sql.getSqlParams());
groupBy & having
Sql sql = new Sql()
.select(
Arrays.asList(
new MinColumn(UserProperties.age, "min_age"),
new MaxColumn(UserProperties.age, "max_age"),
UserProperties.gender
))
.from(UserProperties.TABLE)
.andWhere(CriteriaItemMaker.greaterThanOrEqualsTo(UserProperties.age, 0))
.groupBy(UserProperties.gender)
.having(Having.and(HavingItemMaker.greaterThanOrEqualsTo("min_age", 1)));
assertParamsEquals("SELECT MIN(u.age) AS min_age, MAX(u.age) AS max_age, u.gender FROM user u WHERE u.age >= ? GROUP BY u.gender HAVING min_age >= ?",
Arrays.asList("u.age", 0, "min_age", 1), sql.getSqlParams());
andHaving & orHaving
// andHaving
sql = new Sql()
.select(
Arrays.asList(
new MinColumn(UserProperties.age, "min_age"),
new MaxColumn(UserProperties.age, "max_age"),
UserProperties.gender
))
.from(UserProperties.TABLE)
.andWhere(CriteriaItemMaker.greaterThanOrEqualsTo(UserProperties.age, 0))
.groupBy(UserProperties.gender)
.andHaving(
Having.ors(
Arrays.asList(
HavingItemMaker.greaterThanOrEqualsTo("min_age", 1),
HavingItemMaker.greaterThanOrEqualsTo("max_age", 2))
))
.andHaving(
Having.ors(
Arrays.asList(
HavingItemMaker.greaterThanOrEqualsTo("min_age", 3),
HavingItemMaker.greaterThanOrEqualsTo("max_age", 4)
))
);
assertParamsEquals("SELECT MIN(u.age) AS min_age, MAX(u.age) AS max_age, u.gender FROM user u WHERE u.age >= ? GROUP BY u.gender "
+ "HAVING (min_age >= ? OR max_age >= ?) AND (min_age >= ? OR max_age >= ?)",
Arrays.asList("u.age", 0, "min_age", 1, "max_age", 2, "min_age", 3, "max_age", 4), sql.getSqlParams());
// orHaving
sql = new Sql()
.select(
Arrays.asList(
new MinColumn(UserProperties.age, "min_age"),
new MaxColumn(UserProperties.age, "max_age"),
UserProperties.gender
))
.from(UserProperties.TABLE)
.andWhere(CriteriaItemMaker.greaterThanOrEqualsTo(UserProperties.age, 0))
.groupBy(UserProperties.gender)
.orHaving(
Having.ands(
Arrays.asList(
HavingItemMaker.greaterThanOrEqualsTo("min_age", 1),
HavingItemMaker.greaterThanOrEqualsTo("max_age", 2))
))
.orHaving(
Having.ands(
Arrays.asList(
HavingItemMaker.greaterThanOrEqualsTo("min_age", 3),
HavingItemMaker.greaterThanOrEqualsTo("max_age", 4)
))
);
assertParamsEquals("SELECT MIN(u.age) AS min_age, MAX(u.age) AS max_age, u.gender FROM user u WHERE u.age >= ? GROUP BY u.gender "
+ "HAVING (min_age >= ? AND max_age >= ?) OR (min_age >= ? AND max_age >= ?)",
Arrays.asList("u.age", 0, "min_age", 1, "max_age", 2, "min_age", 3, "max_age", 4), sql.getSqlParams());
limit
Sql sql = new Sql()
.select(Arrays.asList(UserProperties.userId, UserProperties.name, ProjectProperties.name))
.from(UserProperties.TABLE)
.leftJoinOn(ProjectProperties.TABLE, Arrays.asList(UserProperties.currentProjectId, ProjectProperties.projectId))
.orderBy(Arrays.asList(new OrderBy(ProjectProperties.projectId), new OrderBy(UserProperties.userId, true)))
.limit(10);
assertParamsEquals("SELECT u.user_id, u.name, p.name FROM user u LEFT JOIN project p ON u.current_project_id = p.project_id ORDER BY p.project_id"
+ ", u.user_id DESC LIMIT ?, ?", Arrays.asList("$start", 0, "$limit", 10), sql.getSqlParams());
StringSql构造
构造方式与Sql相似，可以查看：tech.ibit.sqlbuilder.StringSqlTest
相关maven依赖包
<dependency>
<groupId>tech.ibit</groupId>
<artifactId>sql-builder</artifactId>
<version>1.1</version>
</dependency>
版权声明: Apache 2
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int main() { int i; char *str = "hu mian yuan"; int length = strlen(str); printf("str ...